1. Technical Field
The present invention relates to manufacturing integrated circuit devices in general, and in particular to manufacturing microfluidic devices. Still more particularly, the present invention relates to a method for manufacturing microscopic canals within a semiconductor integrated circuit device.
2. Description of the Prior Art
Microfluidic devices are semiconductor devices that make use of both the electrical properties of semiconductor substrates and the chemical properties of liquids or gases. Some microfluidic devices contain microscopic canals (or microcanals) with diameters at submicron level. Such microscopic canals allow liquids or gases to flow within a microfluridic device or to flow from one microfluridic device to another. Microfluidic devices having microscopic canals may find applications in optical waveguide, micropneumatics, microhydraulics, etc.
The present disclosure provides a method for manufacturing microscopic canals within a semiconductor integrated circuit device.
In accordance with a preferred embodiment of the present invention, a shallow trench is initially formed in a substrate using a patterned photoresist. After the patterned photoresist has been removed from the substrate, a separation layer, such as a Titanium layer, is deposited on the substrate. Subsequently, a cap layer, such as a Titanium nitride layer, is deposited on the separation layer. Both the separation layer and the cap layer are then polished off from the surface of the substrate. Finally, a Tungsten layer is deposited on the substrate and in the trench such that a microcanal will be formed within the trench as a result.
All objects, features, and advantages of the present invention will become apparent in the following detailed written description.